<!--
 * @Description: 地图
 * @Date: 2022-10-10 15:24:25
 * @LastEditTime: 2022-10-10 15:24:33
 * @FilePath: /测试文档(总结)/48.html
 * @Author: byhzdemacbook-pro-2.local
-->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Create a hover effect</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v2.10.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v2.10.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
<script>
	// TO MAKE THE MAP APPEAR YOU MUST
	// ADD YOUR ACCESS TOKEN FROM
	// https://account.mapbox.com
	mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
    const map = new mapboxgl.Map({
        container: 'map',
        // Choose from Mapbox's core styles, or make your own style with Mapbox Studio
        style: 'mapbox://styles/mapbox/streets-v11',
        center: [-100.486052, 37.830348],
        zoom: 2
    });
    let hoveredStateId = null;

    map.on('load', () => {
        map.addSource('states', {
            'type': 'geojson',
            'data': 'https://docs.mapbox.com/mapbox-gl-js/assets/us_states.geojson'
        });

        // The feature-state dependent fill-opacity expression will render the hover effect
        // when a feature's hover state is set to true.
        map.addLayer({
            'id': 'state-fills',
            'type': 'fill',
            'source': 'states',
            'layout': {},
            'paint': {
                'fill-color': '#627BC1',
                'fill-opacity': [
                    'case',
                    ['boolean', ['feature-state', 'hover'], false],
                    1,
                    0.5
                ]
            }
        });

        map.addLayer({
            'id': 'state-borders',
            'type': 'line',
            'source': 'states',
            'layout': {},
            'paint': {
                'line-color': '#627BC1',
                'line-width': 2
            }
        });

        // When the user moves their mouse over the state-fill layer, we'll update the
        // feature state for the feature under the mouse.
        map.on('mousemove', 'state-fills', (e) => {
            if (e.features.length > 0) {
                if (hoveredStateId !== null) {
                    map.setFeatureState(
                        { source: 'states', id: hoveredStateId },
                        { hover: false }
                    );
                }
                hoveredStateId = e.features[0].id;
                map.setFeatureState(
                    { source: 'states', id: hoveredStateId },
                    { hover: true }
                );
            }
        });

        // When the mouse leaves the state-fill layer, update the feature state of the
        // previously hovered feature.
        map.on('mouseleave', 'state-fills', () => {
            if (hoveredStateId !== null) {
                map.setFeatureState(
                    { source: 'states', id: hoveredStateId },
                    { hover: false }
                );
            }
            hoveredStateId = null;
        });
    });
</script>

</body>
</html>